Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4bf31ead0b2a152…

MALICIOUS

PDF

75.2 KB Created: 2021-06-04 02:40:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 3ffa22b72b4b9a84479021a2a0eb1820 SHA-1: dd59ab7e24e3c1ac5af1178c6b348bfbd52f6a8a SHA-256: f4bf31ead0b2a1524c5dfcfdbb788a7c9e638c5e8c6e6578d2d94d99e722a04d
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://irlanc.ru/pbw?utm_term=student+exploration+building+dna+answer+key+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4457847/normal_5fe13ae911ba2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381287/normal_60643b05e9324.pdfIn PDF document text
    • https://fagowegegex.weebly.com/uploads/1/3/5/3/135315381/4231389.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402488/normal_5feaf7252de5b.pdfIn PDF document text
    • https://gagoxesuv.weebly.com/uploads/1/3/2/6/132681450/5206636.pdfIn PDF document text
    • https://dowikonusinewe.weebly.com/uploads/1/3/4/3/134374018/cc39544.pdfIn PDF document text
    • https://kakewexetoza.weebly.com/uploads/1/3/4/6/134693891/8c0a3d7.pdfIn PDF document text
    • https://fisofomopix.weebly.com/uploads/1/3/4/6/134603918/7167467.pdfIn PDF document text
    • https://zufefofavenubu.weebly.com/uploads/1/3/0/7/130775539/2105191.pdfIn PDF document text
    • https://rixodinek.weebly.com/uploads/1/3/5/3/135392020/xuzesexobosoxa.pdfIn PDF document text
    • https://duvefotod.weebly.com/uploads/1/3/1/3/131380754/vamamek.pdfIn PDF document text
    • https://malabukepi.weebly.com/uploads/1/3/0/9/130969546/9f6eb7faafc.pdfIn PDF document text
    • https://zataxusesuta.weebly.com/uploads/1/3/4/3/134311667/1404347.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379610/normal_5ffc6d09e1963.pdfIn PDF document text
    • https://fugogifozu.weebly.com/uploads/1/3/4/8/134888696/ecf509025c4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455902/normal_604d7ba8afcf3.pdfIn PDF document text
    • https://zapilututok.weebly.com/uploads/1/3/4/3/134341349/3644394.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://mogulazedub.pbworks.com/w/file/fetch/144527394/call_of_duty_ghosts_pc_cheat_codes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2bcb1e2-6a31-4bc2-8559-2555acc4991e/is_100_cacao_healthy.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/70835738-36d5-41d7-aa41-be0612c5db85/20870993745.pdfIn PDF document text
    • http://lekipirunezi.pbworks.com/f/52505937240.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0cacd2b9-3904-46ae-881e-165c9565ec13/fafud.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/36e60f76-489b-45e8-a0c5-4dc9d8b41c80/leledafasigarafuwis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/09be87d3-481d-4f0c-8a5b-5d2fb3fc734c/36902207412.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C2 5776 bytes
SHA-256: 8ca3da8fc0f5fecc7c6a9cf928acd1a8e67c68d68024e83cd05907b4cad87f61
font_01_sfnt_off0000fb92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB92 10532 bytes
SHA-256: a663c4bed85d00f131b0215065b03087e46984705111e325c594c6d12973981d